Re: [PATCH v3 2/4] block: add a read barrier in blk_queue_enter()

[PATCH v3 0/4] block: misc changes · Ming Lei <tom.leiming@gmail.com> · 2017-03-27
[PATCH v3 3/4] block: rename blk_mq_freeze_queue_start() · Ming Lei <tom.leiming@gmail.com> · 2017-03-27
Re: [PATCH v3 3/4] block: rename blk_mq_freeze_queue_start() · Johannes Thumshirn <hidden> · 2017-03-27
[PATCH v3 2/4] block: add a read barrier in blk_queue_enter() · Ming Lei <tom.leiming@gmail.com> · 2017-03-27
Re: [PATCH v3 2/4] block: add a read barrier in blk_queue_enter() · Johannes Thumshirn <hidden> · 2017-03-27
Re: [PATCH v3 2/4] block: add a read barrier in blk_queue_enter() · Bart Van Assche <hidden> · 2017-03-27
[PATCH v3 4/4] block: block new I/O just after queue is set as dying · Ming Lei <tom.leiming@gmail.com> · 2017-03-27
Re: [PATCH v3 4/4] block: block new I/O just after queue is set as dying · Johannes Thumshirn <hidden> · 2017-03-27
Re: [PATCH v3 4/4] block: block new I/O just after queue is set as dying · Bart Van Assche <hidden> · 2017-03-27
[PATCH v3 1/4] blk-mq: comment on races related with timeout handler · Ming Lei <tom.leiming@gmail.com> · 2017-03-27
Re: [PATCH v3 1/4] blk-mq: comment on races related with timeout handler · Johannes Thumshirn <hidden> · 2017-03-27
Re: [PATCH v3 0/4] block: misc changes · Ming Lei <tom.leiming@gmail.com> · 2017-03-29
Re: [PATCH v3 0/4] block: misc changes · Jens Axboe <axboe@kernel.dk> · 2017-03-29

From: Johannes Thumshirn <hidden>
Date: 2017-03-27 12:33:48

On Mon, Mar 27, 2017 at 08:06:56PM +0800, Ming Lei wrote:

Without the barrier, reading DEAD flag of .q_usage_counter
and reading .mq_freeze_depth may be reordered, then the
following wait_event_interruptible() may never return.

Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
---

Reviewed-by: Johannes Thumshirn <redacted>
-- 
Johannes Thumshirn                                          Storage
jthumshirn@suse.de                                +49 911 74053 689
SUSE LINUX GmbH, Maxfeldstr. 5, 90409 Nï¿½rnberg
GF: Felix Imendï¿½rffer, Jane Smithard, Graham Norton
HRB 21284 (AG Nï¿½rnberg)
Key fingerprint = EC38 9CAB C2C4 F25D 8600 D0D0 0393 969D 2D76 0850

`h`	back out one level
`j`	next message in thread
`k`	previous message in thread
`l`	drill in
`Esc`	close help / fold thread tree
`?`	toggle this help